docs: def preflight(self):
          """Handles request authentication"""
          origin = self.request.headers.get('Origin', '*')
          self.set_header('Access-Control-Allow-Origin', origin)
  
          headers = self.request.headers.get('Access-Control-Request-Headers')
          if headers:
              self.set_header('Access-Control-Allow-Headers', headers)
  
          self.set_header('Access-Control-Allow-Credentials', 'true')